System for controlling electric motors.



Ni. 786,424. PATENTED APR. 4. 1905.

H. H. CUTLER. SYSTEM FOR CONTROLLING ELEGTRIG MOTORS.

APPLIOATION FILED JULY 6, 1903.

2 SHEETS-SHEET 1.

PATENTED APR. 4, 1905.

H. H. CUTLER. SYSTEM FOR CONTROLLING ELEGTRIG MOTORS.

APPLICATION FILED JULY 6, 1903.

2 SHEETS-SHEET 2.

UNITED STATES Patented April 4, 1905.

PATENT OEEIcE.

HENRY H. CUTLER, OF MILWAUKEE, \VISCONSIN, ASSIGNOR TO THE CUTLER-HAMMERMANUFACTURING COMPANY, OF MILWAUKEE, WVISCONSIN, A CORPORATION OFIVISCONSIN.

SYSTEM FOR CONTROLLING ELECTRIC MOTORS.

SPECIFICATION forming part of Letters Patent No. 786,424, dated April 4,1905.

Application filed July 6, 1903. Serial No. 164,380.

To a whom it um/y concern.-

Be itknown thatl, HENRY H. CUTLER, a citi- Zen of the United States,residing at Milwaukee, in the county of Milwaukee and State ofVisconsin, have invented a certain new and useful Improvement in Systemsfor Controlling Electric Motors, of which the following is a full,clear, concise, and exact description, reference being had to theaccompanying drawings, forming a part of this specification.

My invention relates to a system particularl y designed for controllingelectric motors; and it is a modification of the system disclosed in myapplication filed April 15, 1903, Serial No. 152,701.

The system permits the actuation of the controller for the electricmotor from a distant point, and therefore it is appropriate forcontrolling the operation of electric motors which propel electricvehicles and for operating a train of cars upon the multiple-unit plan.

The preferred embodiment of the present invention employs a plurality ofelectromagnetic windings which are adapted to repond to currents ofdifferent amperes and which are connected in series in acontrollingcircuit. These windings operate the elements of anelectric-motor controller or other suitable instrumentalities. Theamperage of the current delivered to the controlling-circuit is variedthrough the agency of suitable means to selectively actuate theelectromagnetic windings, and thus operate the elements of theelectrio-motor controller.

One system which 1 have worked out for the purpose of disclosing myinvention is illustrated diagrammatically in the accompanying drawings.In these drawings I have separated the controlling-circuits from thepowercircuits in different figures, and the views in said drawings areas follows:

Figure 1 is a diagrammatic view of the car or controlling circuit withcertain of the in strumentalities actuated by the electromagneticwindings included in said circuit. Fig. 2 is a diagrammatic view of thepower-circuit for the electric motors and the switches for said circuit,which are controlled by the electromagnetic windings on thecontrolling-circuit above mentioned. Fig. 3 is a diagrammatic view ofone form of interlocking lever for the series-parallel switch.

In Fig. I, to'which I. will first refer in describing my invention, isshown the complete equipment of a single car. This circuit arrangementis duplicated in each of the cars, and therefore its use in operating atrain of cars on the multiple-unit plan will be readily appreciated inthe light of the description of the system which follows. At each end ofthe car is preferably situated a controller K', which may be of anyform. The controller illustrated herein has segments 7 Z1 Xi, and If.and two sets of contacts 71 and k, respectively. Between the sets ofcontacts I? are connected the sections of the resistance A and betweenthe series of contacts /r" are connected the sections of resistance 7n.An arm Z5, having handle if, is centrally pivoted, so that it is movableover said contacts or segments, and carries brushes 71: and 7c. The armnormally rests in what is termed the central position, as shown, andwhen it is in such position the series of contacts Z and segments Z" and71 are situated upon one side of said arm, while the other series ofcontacts 7: and segments If and Z1" are situated on the other sidethereof. The brushes carried by said arm are disposed to engage thesegments and the contacts, and when said arm is moved by the handle inthe direction indicated by the arrow the brush K will connect thecontacts 71' with the segment is, while the brush 71;" will connect thesegments 7" and 7:"; but if the arm be moved in the reverse directionthen the brush 7: will connect the contacts 71; with the segment 76,while the brush A will bridge segments 7: and 7c. The two controllersare connected by four wires 16, 17, I8, and 19, which in practice wouldpreferably be formed into a single cable. The wire 16 connects thecontact of each resistance which is farthest removed from the brush iswhen the controller-arm is at its ini tial position with the samecontact of each of the other resistances. The segments 75 and Z1" ofeach controller are all connected by the wire 17. The segments Z2 and Z/of the two controllers are connected by the wire 18, while the segments7:? and Z1 are connected by the wire 19. The last contact of theresistance 71 is connected by the wire 20 with trolley T, and thesegment 70 is connected with the ground (1 by the wire 21. Between thewires 18 and 19 is connected the car or controlling circuit comprisingthe wire 22, which is connected with the wire 19, and the wire 23, whichis connected with the wire 18. Suitable switches 24; are preferablyarranged in the car or controlling circuit, so that the said circuit maybe disconnected from the controllers, if desired.

By reference to Fig. 2 it will be noted that the two motors are shown,one of which has armature (L and lield 6, while the other has armature cand lield (Z, and therefore a reversing-switch is provided for each ofsaid motors, as well as separate resistance-switches.

\Vith reference to Fig. 1 the solenoids m and a: control thereversing-switches for the motor-armature (1/, while the solenoids andcontrol the reversing-switches for the motorarmature c. The solenoids a"and 7' control the sections of resistance for the armature a, and

the solenoids and r control the switches for the sections of resistancefor the armature c. The switches for controlling the series and parallelrelations of the two motors in curcuit have the solenoid s for actuatingthe series switch and the solenoid 7) for operating the parallel switch.The solenoids a", o 9", and 0" are differently wound, so that solenoidsv" and 9"" will operate their switches under a lower amperage than thesolenoids 1' and 1".

The solenoids for the reversing-switches each preferably have an upperwinding, which is coarse, and a lower winding, which is line. Thesolenoid on has coarse winding'w and line winding in, and the solenoidhas upper coarse winding m and lower line winding m So, also, thesolenoid g has upper coarse winding ;1 and lower line winding 1/, andsimilarly the solenoid has upper coarse winding .2 and lower linewinding .2. The line windings '10 11: 7 of the solenoids of thereversingswitchcs are preferably connected in series between the wires20 and 21 by wires 25 and 26, so that they are constantly supplied withcurrent from the trolley T and the ground G. The coarse windings w, a",2/, and .2" of the solenoids of the reversing-switches, the solenoids9", r, r", and 9" of the resistanceswitches, and the solenoids s and 7.)of the series-parallel switches are all connected in series between theopposite sides of the controlling-circuit. So, therefore, the finewindings of the solenoids of the reversing-switches are constantlysupplied with current from the main line, while the coarse windings ofsaid solenoids are supplied with current from the controlling-curcuit.The two windings of each of the solenoids of the reversing-switches arepreferably such that when the current is flowing therethrough theirmagnetizingeliect is equal.

As just stated, the line or lower windings of the solenoids of thereversing-switches are constantly supplied with current from the mainline, and therefore the How of the current therein is always in the samedirection; but the direction in which the current flows through theupper or coarse windings may be varied by the manipulation of thecontroller, as will be hereinafter explained. The upper winding of eachof said solenoids is so wound that when the current flows therethroughin one direction the two windings of said solenoids tend to produce thesame polarit \&-that is, for instance, if the winding w of solenoid '10tends to produce a north pole at the top and a south pole at the bottomthen the lower winding also tends to produce a north pole at the top anda south pole at the bottom; but if the current flows through said upperwinding in the reverse direction then said upper winding tends toproduce an opposite polarity of the solenoid from that which the winding10 tends to produce, and therefore said winding '10 would tend to createat the top a south pole and at the bottom a north pole, while windingwe" would tend to produce a north pole at the top and a south pole atthe bottom. In the first instance when the windings of the solenoid tendto produce the same polarity one winding would assist the other and thesolenoid would raise its core; but when said windings tend to produceopposite polarities then the solenoid would remain inert and its corewould not be lifted, as the lield excited by one winding wouldneutralize or destroy the effect of the lield excited by the other. Theupper or coarse windings w, :1", y, and .2 of the several solenoids aresuch that when the current flows on the controlling-circuit in onedirection the windings w and 1 will tend to produce the same polarity astheir corresponding windings w and 9/ respectively, and therefore thesolenoids w and y will be energized and lift their cores, while thewindings a" and 2 will tend to produce opposite polarities to thewindings a? and .2, and therefore the solenoids a: and will remain inertand not lift their cores or plungers. If the current be reversed uponthe car-circuit, then the action of the solenoids of thereversingswitches will be reversed, or the solenoids w and '2 willremain inert while the solenoids m and .2 will be energized.

To eiiect the reversal of the flow or polarity of the current on thecontrolling-circuit, the arm of the controller is made so as to bemovable in ditfercntdirections from the central or initial position, andwhen it is moved u pwardly say in the direction of the arrow then thecurrent flows on the controlling-circuit in a reverse direction to thatwhich it would if the arm were moved downwardly.

In movement of the arm of the controller in either direction thegreatest amount of resistance is included in the controlling-circuit bysaid controller when the brush 7: engages the first contact of either ofthe sets of contacts 70 or in. As the arm is further passed from itsnormal position the sections of the resistance included in circuit arecut out one by one as the brush 71? engages the successive contacts. Ofcourse as the resistance is removed from circuit the current on thecontrolling-circuit is increased. There fore, it will be noted that thecurrent upon the controlling-circuit may be varied at will by themanipulation of the controller-arm, and the direction in which saidcurrent is flowing upon said circuit will depend upon the side to whichthe controller-arm is moved from its initial position.

\Nith each of the several solenoids referred to in this system isarranged a switch I, adapted to close a shunt-circuit around thesolenoid with which it is associated, and in said shuntcircuit isconnected a resistance 1, which when the shunt-circuit is closed willprotect its solenoid from excessive currents. The switches Z are solocated that they are actuated to close the shunt-circuits by pins uponthe plungers of the solenoids when said solenoids are energized.

Between the plungers or cores of the solen oids w and of onereversing-switch is preferably arranged in practice an interlockinglever or other means to insure the lowering of one core when the othercore is raised, and normally the two cores set in an intermediateposition. A similar interlocking mechanism or lever is arranged betweenthe plungers 1 and of the other reversing-switch.

The solenoids a and 7) of the series and par allel switches are wound sothat a larger current will be required to energize the solenoid p thanthe solenoid 3. Between the plungers or cores of these solenoids is alsopreferably situated in practice an interlocking mechanism like that ofthe plungers of the solenoids of the reversing-switches, save that saidinterlocking mechanism between the plungers of the solenoids s and 1)permit a slight freedom of movement of the plunger of the solenoid 32.One form of interlocking lever which may be employed between theplungers of the series and parallel solenoids is diagrammatically shownin Fig. 3.

The plungers or'cores of each of the solenoids carry suitable contactdevices or brushes, which are arranged to bridge the terminals of theirswitches, and these contacts and terminals I will now designate byreference characters. The plungers or cores of each of the solenoids ofthe reversing-switches carry at both their lower and upper ends acontact which is adapted to bridge suitable terminals when the plungeris raised. The core of solenoid w carries at its upper end contact 27,adapted to bridge terminals 28 and 29, and at its lower end a contact orbrush 30, adapted to bridge terminals 31 and 32. At the upper end of thecore of solenoid :1: is a contact arranged to engage terminals 34 and35, and at the lower end of said plunger is a contact 36, situated so asto engage terminals 37 and 38 when the plunger is raised. The plunger ofthe solenoid ;1 has contact 39 at its upper end for connecting terminals40 and 41 and a contact at its lower end adapted to bridge the terminals43 and 44. The contact 45 at the upper end of the plunger of solenoid isadapted to bridge terminals 46 and 47, and the contact 48 at the lowerend of said plunger is arranged to connect terminals 49 and 50. Theresistance-solenoids 9', r 7*, and 1" each have a contact upon theplunger of their solenoid, which is arranged to bridge suitableterminals for cutting out sections of resistance. The plunger ofsolenoid 1- has contact 51 adapted to bridge terminals 52 and 53 to cutout asection of the resistance from one motor, and the plunger ofsolenoid W has contact 54 adapted to bridge terminals 55 and 56, so asto cut out another section of the resistance from said motor. Thesolenoid 0' has its plunger provided with a contact 57, arranged tobridge when raised the terminals 58 and 59, so as to cut from thecircuit of the armature c of the other motor a section of the resistancetherefor, and another section of the resistance for the lastmentionedarmature is adapted to be removed from the circuit by contact 60,carried by the plunger of solenoid r and arranged to bridge terminals 61and 62. The plunger of the solenoid s of the series switch has at itsupper end a contact 63, arranged to bridge terminals 64 and 65 when theplunger is raised, and at its lower end asecond contact66,adapted tobridge terminals 67 and 68 when said plunger is in its upper position.Said plunger also carries another contact, 69, which when the plunger islowered bridges terminals 70 and 71 in the controlling-circuit. Theplunger of solenoid 7) has at its upper end a contact 72, which when theplunger is raised bridges terminals 72) and 74, and at its lower endacontact 75, which when the plunger is in a similar position bridges theterminals 76 and 77. The plunger of the parallel switch also has at itslower end acontact or brush 78, arranged to bridge terminals 79 and 80when the plunger is raised, and a brush or contact 81, which is situatedso as to connect terminals 82 and 83 when the plunger is in anintermediate position, but to disconnect said terminals when the plungeris completely raised or lowered.

1 will now refer to the power-circuits for the motors as shown in Fig.2. In said ligure are shown generally the solenoid-switches forestablishing the different relations between the motors and thecircuits. In order to more readily disclose these circuits and theoperation of the system, I will now follow the powercircuits from themotor. In the first place let it be assumed that the plungers of thesolenoids w and 1 have been energized, so that the contacts carried bytheir plungers will bridge their respective terminals, and that thesolenoid of the series switch is energized. \Vith the switches thusclosed the current will flow from trolley T by wire 84 to terminal 28 ofthe reversing-switch. Thence it will cross the contact 27 to terminal 29and flow to terminal 37. From here it will pass over wire 85 to thearmature a and after traversing said armature will be conducted by thewire 86 to the terminal 32. By crossing the bridge or contact 30 toterminal 31 it will flow over conductor 7, through the field b, and overwire 88. From wire 88 it will cross sections and r of the resistance forthe armature (1/, controlled by solenoids r and r Thence it will pass byconductor 89 to terminal 68 of the series switch, and cross the contact66 thereof to the terminal 67, whence it will be conducted by wire 90 tothe terminal 64 of said series switch and cross from said terminal bycontact 63 to terminal 65. Now it will pass over conductor 91 and flowthrough sections r and o of the resistance for the armature of the motor0, which are controlled by solenoids 1" and 9', respectively, to thewire 92. After traversing the field d from the wire 92 the current willflow through the wire 93 to terminal 43 of the reversing-switch for thearmature of the motor 0 and pass by contact 42 to terminal 44. Fromterminal 44 it will pass by wire 94 to the armature 0, and aftertraversing said armature, it will flow by wire 95 to terminals 49 and 41of the reversingswitch for said armature. The current will then crosscontact 39 to terminal 40 and thence flow over conductor 96 to theground G.

If the solenoids :1; and of the reversingswitches be energized, then thecurrent will flow through the armatures of the motors in the reversedirection and cause an opposite rotation thereof. In this instance thecurrent will flow from terminal 28 of the reversingswitch of thearmature (a over wire 97 to terminal 35 and thence by contact 33 andterminal 34 to terminal 32. From terminal 32 it will flow through wire86, armature (1, and wire 85 in the reverse direction to that which itdid before. After reaching terminal 217 by wire 85 it will cross contact36 and thence pass from terminal 38 to terminal 31. From here it willpursue the same course as before until it reaches the terminal 43 of theother reversing-switch. From terminal 43 it will pass to terminal 50 andthence through contact 48 to terminal 49. From terminal 49 it will flowthrough wire 95, armature 0, and wire 94 1D the reverse dlreetlon tothat which it before pursued, and thence after passing through terminals44 and 46 it will cross the bridge or contact 45 to terminal 47, whenceit will follow conductors 97 and 96 to the ground.

As before stated, the solenoid 9' controls section of resistance o Theterminals of the switch controlled by said solenoid are situated in ashunt-path around said section of the resistance, so that when thecontact bridges said terminals the section of the resistance is removedfrom circuit. The terminals of each of the other switches are similarlyarranged in shunt-paths around one or the other different sections ofthe resistances, so that each solenoid-switch controls a section of theresistance for one or the other of the armatures (a and 0. As beforestated, the sections o and r of one resistance are for armature a, andtherefore when the solenoids o" and r are onergized these sections areremoved from the circuit ofthe armature (,6. So, likewise, when thesolenoids 7"" and 0" are energized the sections 0' and 9' of the otherresistance are removed from the circuit of the armature c.

if the parallel switch be closed instead of the series switch by thecnergization of the solenoid p, then the current after traversing thearmatures n. and field I) by the paths heretofore disclosed will flowfrom terminal 76, connected to wire 89, across bridge 75 to terminal 78,and thence by wire 98 to the ground. The current from the other motorwill flow from the wire 97, connected with the trolley, over wire 99 toterminal 74, and after cross ing contact '72 to terminal 73 it will flowby wire 91 through the same path before traced from the armatures c andfield (6 to the ground G.

The motor-circuits having now been explained, I will refer to thecontrolling-circuits (shown in Fig. 1) and describe how the differentsolenoids are actuated from the controller and the operation thereofwhen the controller is being manipulated. Let it be assumed that sixamperes are required for the energization of the solenoids of thereversing-switches. Then when the controller-arm has been movedsul'liciently to cut out enough resistance to give a current upon thecontrol]ing-circuit of six amperes one of the solenoids of eachreversing-switch will be energized, while the othersolenoid of eachreversing-switch will re main inert by reason of their construction, asheretofore explained. Let it be assumed in this instance that thecontroller-arm has been moved to the side thereof which will send thecurrent upon the controlling-circuit in adirection to energize thesolenoids w and y. Of course if it be desired to energize the solenoidsa: and .2, so as to produce a reverse movement of the armatures of themotor, then the said controller-arm would be moved to the opposite side.The solenoid s of the series switch also responds under a current of sixamperes. \Vith the series and reversing switches thus closed the motorswill be started and run in series. It is then time to remove theresistance from the armatures of said motors, and therefore thecontroller-arm will be further moved, so as to increase the current uponthe controlling circuit to nine amperes, under which amperage thesolenoids r and 1' will respond. On a still further increase of thecurrent to eleven amperes the solenoids 1' and 0" will close theirswitches, and then all the resistance will be removed from the circuitsof the armatures. At this stage of running the motors when they haveacquired their speed 7 it is desirable to run them in parallel. Thesolenoid p is wound to respond to'a current of fifteen amperes, andtherefore the control ler-arm is moved to the succeeding contacts of itsresistance until the amperage upon the car-circuit has been increased tofifteen amperes, so as to energize the solenoid p, whereupon its corewill lift, and the switch in the motor-circuitcontrolled thereby will beclosed. At an intermediate position of the plunger of the parallelsolenoid in being raised the contact 81 carried thereby bridgesterminals 82 and 83 and closes a shunt-path 100 around theresistance-solenoids 0*, 9 ,9 and 7" and solenoid s of the seriesswitch. Thereupon the current in these solenoids is so reduced that theydrop their cores. The interlocking lever employed in practice betweenthe plungers of the series and parallel solenoids gives the plunger ofthe parallel solenoid suflicient freedom of movement to permit it toclose the shunt-path around the series solenoid before said lever isactuated by the parallel solenoid to lower the plunger of the seriesswitch. When the plunger of the parallel switch has been raisedcompletely, connection between the terminals 82 and 83 by contact orbrush 81 has been broken, and a new shunt-path 101 around all of thesolenoids upon the controllingcircuit, save the parallel solenoid p, isestablished by the contact 69 on the plunger of the series switch, whichengages terminals 7 0 and 71 when the series plunger is lowered, and thecontact 78 upon the plunger of the parallel solenoid, which bridgesterminals 79 and 80. A path 102 is established by contact 78 andterminals 79 and 80 of the parallel switch, so as to separately shuntthe solenoids of the series switch. In the shunt-path 101 is situated aresistance 0, and with this resistance connected in the relationdescribed a further increase of the total current upon thecontrolling-circuit say to eighteen amperes will be required before thesolenoids 1" and 0' again respond to cut the sections of resistancecontrolled by their switches from the circuits of the motors, and astill further increase of the current upon the controlling-circuits totwenty-two amperes will be required before the solenoids 0' and 1" areenergized and cut out the respective sections of resistance controlledthereby. \Vith the resistance 0 in circuit the current will dividebetween said resistance and the solenoids in parallel therewith, andapproximately half of the total current on the controlling-circuit willflow through each.

In the first part of this specification it was stated that twocontrollers are preferably arranged in each car. This is so that the carmay be operated from either end, and the controllers are preferablyconnected in circuit in such a manner that corresponding movements ofthe controller-arms will produce similar movements of the train from thestandpoint at which it is being operated that is, if movement of thecontroller-arm to the right at one end of the car will produce a forwardmovement thereof then a similar movement of the controller-arm at theother end of said car will produce an opposite movement of the car. Thecar is also provided with a train-line composed of wires 103 and 104 forpassing the current from one car to the other, so that the motors uponeach of the several cars may be controlled from a singlemaster-controller situated at the forward end of the front car. Thetrain-line upon each car is provided with suitable couplings at itsends, so that it may be connected to the train-lines of the cars towhich it is coupled. These couplings are preferably of such form thatthey will always connect the same wires of the train-lines. The wire 103of-the train-line is connected by wire 105 with the wire 18, and thewire 101 is connected by the wire 106 with the wire 19, so that thetrain-line is supplied with current from the ground G through the wires18 and 19. Suitable switches 107 are preferably interposed in the wires104C and 105 to permit the train-line and controlling-circuit to bedisconnected from each other, if desired. It will be readily understoodhow the controlling-circuits of several cars in a train may be suppliedwith current from the motor or forward ear, and said current beingsupplied to said controlling-circuit from the motor-car its polarity andstrength will be completely within the control of the operator of themaster-controller at the forward end of the front car.

In the system disclosed the motors can be perfectly controlled from thesingle mastercontroller, and by reason of placing or connecting thedifferent windings in series uniformity of action in the system will beinsured. As the power-circuit is supplied with current from the mainline, which carries a large current, the current-carrying parts of thesystem and controller will necessarily be made larger than would be thecase if the current were supplied from a generator or other source uponthe car.

The system which I have disclosed is only one form of my invention, andit may therefore be changed in many ways. The system is equallyapplicable for controlling motors which are employed for other purposesthan operating motor-vehicles, and the windings may be used to operateor control other instrumentalities than the elements of anelectric-motor controller. Therefore it will be understood that I do notlimit myself to the details of construction which I have herein shownand described merely for the purpose of setting out my invention tothose skilled in the art.

I claim- 1. The combination with a controlling-circuit, ol a pluralityof electromagnetic windings connected therewith in series, means forvarying the polarity and strength of the current upon saidcontrolling-circuit to selectively actuate said electromagneticwindings, and the elements of an electric-motor controller operated bysaid windings.

2. The combination with a controlling-circuit, 01 a plurality ofelectromagnetic windings connected therewith in series, areversing-switch and 1notor-speed-varying instrumentalities controlledby said windings, and means for varying the electrical conditions onsaid controlling-circuit to selectively actuate said windings.

3. The combination with a controlling-circuit, of a plurality ofelectromagnetic windings adapted to respond to currents of difl erentcharacter and connected therewith in series, suitable instrumentalitiesarranged to be controlled by said windings, and means for varying atwill the polarity and other characteristics of the current supplied tosaid controlling -circuit to selectively actuate said windings.

4. The combination with a supply or power circuit, of acontrolling-oircuit, a plurality of electromagnetic windings adapted torespond to different current conditions and connected with saidcontrolling-circuit in series, and suitable means for transforming thecurrent from said sup ')ly-circuit as to strength and polarity into acurrent suitable for use upon said controlling-circuit to selectivelyactuate said electromagnetic windings.

5. The combination with a suitable supply-circuit, of acontrolling-circuit connected therewith, a pluralityot' electromagneticwindings arranged in series in said controlling-circuit and responsiveto currents of different strengths, suitable instrumentalitiescontrolled by said windings, and means for varying at will the strengthand polarity of the current upon said controlling-circuit.

(5. The combination with a suitable supply-circuit, ot' acontrolling-circuit connected therewith, a plurality of electromagneticwindings arranged in series in said controlling-circuit and responsiveto currents of different strengths, an electric-motor controllercontrolled by said windings, and means for varying at will the strengthand polarity of the current upon said controlling-circuit.

7. The combination with a supply-circuit, of a eontrolling-circuitconnected therewith,

a plurality of electromagnetic windings arranged in series in saidcontrolling-circuit, an armatureresistance controlled by said windings,a reversing-switch also controlled by said windings, and means forvarying at will the strength and polarity of the current upon saidcontrol]ing circuit.

8. The combination with a suitable supplycircuit, of acontrollingcircuit connected therewith, a plurality of electromagneticwindings arranged in series in said controllingeircuit and responsive tovariations in the strength of the current upon said controllingcircuit,an armature resistance controlled by said windings, a reversing and aseries-parallel switch also controlled by said windings, and means forvarying at will the strength and polarity of the current upon saidcontrollingcircuit.

9. The con'ilnnation with a suitable supplycircuit, of acontrollil'ig-circuit, a plurality of electromagnetic windings arrangedin series in said controlling-eircuit and responsive to variations inthe strength of the current upon said controllingeircuit, an armatureresistance controlled by said windings, a series and a parallel switchalso controlled by said wind ings, said parallel switch being adapted tocontrol the current which traverses the windings controlling saidarmature resistance and said series switch, and means for varying atwill the strength and polarity of the current upon said car-circuit.

10. The combination with a suitable supplycircuit, of acontrollingcircuit connected therewith, a plurality of electromagneticwindings arranged in series in said controllingcircuit and responsive tovariations in the strength of the current upon said controllingcircuit,an electric-motor controller having its elements controlled by saidwindings, and conductive means for varying at will the strength andpolarity of the current supplied to said controlling-circuit from saidsupplycircuit.

11. The combination with a suitable power'or supply circuit, of one ormore electric motors connected therewith, acontrolling-circuitconnectedwith said power-circuit, a plurality of electromagnetic windingsarranged in series in said controlling-circait and responsive tovariations in the strength of the current upon said controlling-circuit,an armature resistance for said motor controlled by said windings, areversing-switch for said motor also controlled by said windings, theoperation of said switch being dependent upon the direction of the flowot' the current upon said controlling-circuit, and means for varying atwill the strength and polarity of the current upon saidcontrolling-circuit.

12. The combination with a suitable power or supply circuit, of two ormore electric motors connected therewith, a control]ing-circuit alsoconnected with said power-circuit, a plurality of electromagneticwindings arranged in series in said controlling-circuit and responsiveto variations in the strength of the current on the saidcontrolling-circuit, an armature resistance for said motors controlledby said windings, and switches for connecting said motors in a series orparallel relation also controlled by said windings, and means forvarying at Will the strength and polarity of the current upon saidcontrolling-circuit.

13. The combination with a suitable power or supply circuit, of two ormore electric motors connected therein, a controlling-circuit connectedWith said power-circuit, a plurality of electromagnetic windingsarranged in series in said controlling-circuit and responsive tovariations in the strength of the current upon said controlling-circuit,an armature resistance for said motors controlled by said windings, areversing and a series-parallel switch also controlled by said windings,said series-parallel switch being adapted to connect said motors eitherin series or parallel relation, and the operation of saidreversingswitch being dependent upon the direction of the flow of thecurrent upon the controllingcircuit, and conductive means for varying atwill the strength and polarity of the current upon saidcontrolling-circuit.

M. The combination ,with asuitable circuit,

16. The combination with a controlling-circuit, of a plurality ofelectromagnetic windings connected therewith in series and adapted torespond to currents of different character, means for varying thecharacter of the current upon said controlling-circuit,and switchesadapted to connect a resistance in shunt round each responding solenoid.

In witness whereof 1 have hereunto sub scribed my name in the presenceof two witnesses.

HENRY H. CUTLER.

\Vitnesses:

T. E. BARNUM, F. R. BACON.

